1. Field of the Invention
The present invention relates to an adapter for wiring, and more specifically to the structure of an adapter for wiring which enables insertion holes for cables and cable tubes to be easily perforated and further to be easily closed hermetically.
2. Prior Art
A wiring box in which underground cables are arranged is usually made of a concrete. Prior to burying it under the ground, insertion holes are perforated in the side walls of the wiring box using a drill or the like and cable tubes are inserted in the insertion holes. When the cables are to be passed through the walls of a building insertion holes are perforated in the walls using a drill or the like.
However, the wiring boxes and walls of a building have been so rigidly constructed using concrete that extended periods of time and laborious work are needed to perforate the insertion holes. After the cable tubes and cables are inserted in the insertion holes the insertion holes are hermetically closed by applying mortar or the like often resulting in defective construction work in that the mortar is applied in varying amounts.